Process for moistening and cooling dextrin.



H. WULKAN. PRocEss Foa MolsTENING AND ACOOLING DEXTRIN.

`APPLICATION FILED M16-i3. 191,3.

Patented May 18, 1915.

HEINRICH WULKAN, 0F.BUDAPEST, AUSTRIA-HUNGARY, ASSIGNOR TO DEXTBIN AUTOMAT, GESELLSCHAFT M. B. H., RATION OF AUSTRIA-HUNGARY,

0F VIENNA, .AUSTRIA-HUNGARY, A CORPO- PRQCESS FOR MISTENING AND COOLING- DEXTRIN.

Application led August 13, 1913. Serial No. 784,635.

To all whom it may concern:

Be it known that I, HEINRICH WULKAN, a citizen of the Empire of Austria-Hungary, residing at Budapest, in the Empire of Austria-Hungary, have invented a new and useful Improvement in Processes for Moist- -ening and Cooling Dextrin, of which the following is a specification.

This invention relates to a process and apparatus for moistening and cooling dextrin; and it comprises a process of moistening and cooling dextrin which comprises subjecting the dextrin while maintained 1n a state of constant agitation to the laction of a mixture of steam and air or of .supersaturated air while maintained at a temperature below about 600 C. and particularly between 40 to 50 C. by means of a cooling medium which is kept from direct contact with the dextrin itself; and it also comprises an apparatus in which provision is made for the introduction of a mixture of air and steam or of supersaturated air together with agitating means for agitating the dextrin and means for cooling the dextrin without direct contact of the cooling medium with the dextrin being treated; and it further comprises certain novel features of construction and arrangement of parts and certain novel features of the process; all as more fully hereinafter set forth and as claimed.

In the moistening of dextrin it is dilicult to prevent the formation of a thick viscous mass which is dilicult to handle and which is frequently also diicult to convert into thinner so-called solutions of dextrin such as are used in the arts. Since dextrin is usually soluble in water it is usually necessary to keep it entirely free from moisture until such time as it is cording to the process of thepresent invention, it is possible to lmoisten dextrin without the formation ofsuch a thick gummy mass so that the moistened dextrin still retains its finely divided powder form, in which form it can be readily'kept and subsequently utilized by the addi-tion of further water or in other suitable manner. The

Specification of Letters Patent.

desired for use. Ac

Patented May 18, 1915.

presence of the added water in the powdered or ely divided dextrin makes this material a particularly valuable material for subsequent use, containing as it does the added moisture in an unobjectionable form, and being Capable of use without the necessity for the subsequent addition of as large amounts of water as would otherwise be necessary, and resulting in smooth and homogeneous solutions.

In carrying out the process of the present invention, the dextrin is maintained in a state of constant agitation and is treated with a mixture of steam and air or supersaturated air while maintained at a suitable temperature. The mixture of 'steam and air injecting direct steam-into a current of compressed air, or by conducting air through a vessel in which steam is formed or is introduced, or a current of air may be sucked in by a steam injector; or other suitable means for forming the mixture of steam and air or the supersaturated air can be used. After the dextrin is cooled to a temperature below 60 C. and advantageously below 50 C. the mixture of steam and air is slowly introduced into the agitated dextrin and vthe temperature ofthe dextrin is maintained at about 40 to 50 C. during the introduction. During the introduction of the steam, or of the hot supersaturated air and in order to avoid the tendency toward increase in temperature due to the temperature of the entering steam, the dextrin is kept in lively motion and subjected to an energetic cooling so that the specified temperatures are not exceeded. The cooling of the dextrin is not effected by the introduction of the cooling medium through the dextrin, but is effected by external cooling of the vessel in which the dextrin is contained, the cooling being effected by cold air which isl in turn cooled by cold water.

In the accompanying drawings which illustrate the present vinvention is shown an apparatus in which the process of the presen't invention can be carried out. In this apparatus the vessel A is shown as provided or the supersajturated air can be prepared by also discharges. The

with a stirrer B driven by means of bevel gears M and the pulleys N'. of the vessel A is a false bottom C which is provided with a large number of small perfor-ations and which forms a sieve through which the mixture of air and steam can pass. Surrounding the vessel A are the two jackets D and E and through the outer jacket E provision is made for the circulation of cold water which enters at c and escapes at fi, while through the inner jacket D air is circulated, entering at a. and being discharged at b.' A steam injector is shown at F in to Awhich high pressure steam is admitted through e and into which the air outlet b injector discharges through the` 3-way valve f by means of ,which the mixture of. air and steam can be either discharged to the Vatmosphere or admitted in any desired amount to the bottom of the chamber A below the false bottom C. An outlet g is provided from the bottom of the chamber A and communicating with the steam and air ymixture inlet pipe for carrying away 'any condensed steam from the ap-` paratus. The chamber A is provided with I a hood Gr in the top tising'the process o an opening H for charging and an opening I fordischarging, and 1s also provided with of which is a lter h.,

and with aathermo'meter lm/'for indicating the temperature ofl the apparatus.' vIn the paratus and in practhe present invention in it, the dextrin iis charged into the apparatus through the opening H; andas constantly agitated by means of the stirrer B. Cold water isr circulated through the outer casing E and air is drawn through the inner jacket and out through the outlet lb by means of the steam injector F. If the temoperation of this a perature ofthe dextrin is higher than about' athen air is sucked through the through the outlet b inner jacket and out by means of thesteam injector F and the mixture ofsteam and air or the supersaturated airis allowed to es capeto theatmosi l phere-through the 43-wayvalve f until the i through C into temperature has been reduced to about 40 to-50`-C. which is the temperature found to be particularly advantageous in carrying When thistemperature has been reached, the cock f is turned to admit the `miittureof steam and air into the bottomvof the easing fromwhich it passes up the perforated false bottom or sieve tated and constantly cooled. .The amount of excess-of the steamand ailfmixture e--to `the-atmosphere dury suitable regulation ofl the mixture of steam and air and the rate of cooling can be controlled by. means of thek steam injector fI and the 3-way .valve any being ermitted to esca mg the process.

In the bottom` the dextrin which is constantly agi-I the injector and the amount cf the steam and. air mixture or the degree of supersaturation of the air introduced into the ap aratus, the dextrin can be maintained at tllfe temperatures speciied throughout the process until the desired moistening has been eiected.

4While other means for cooling dextrin might be utilized, yet it has been found that the method described and illustrated by the drawing has been found advantageous. Any steam which may condense and separate out in the apparatus or inA the inlet pipe will find its way out through the condensed` water outlet g,

vlarly valuable product, as already indicated.

In carr out the process of the present invention it isessential that the dextrin be subjected tothe necessary cooling inorder that its temperature may not rise above from ,40 to 50 C. or a maximum of about 1. The process of moistening dextrin which comprises subjecting the dextrin while maintained in a state of agitation to the actionlof heated supersatu-rated air and to the action of a coolingk medium suilicient' to maintain the temperature of the dextrin .below about 60 C.without direct contact of the cooling medium with the dextrin treated. 2. The. process of moistening dextrin which comprises subjecting I the dextrin while maintained in a state of agitation to the action of heated supersaturated air and to the action of. a cooling medium suiiicient to maintainthe temperature of the dextrin between 40 and 50 C. without direct con- The hood Gr and' vthe filter h prevent the dextrin from escapioo tactof the cooling medium with the dextrin treated. i.

The of moistening dextrin .which comprises maintaining the dextrin in constant agitationin a vessel maintained by external cooling means at a temperature between 40 and 50C. and introducing into the dextrin. while so cooled and 'agitated a heated supersaturated air mixture in regulated amounts. 'i

4.v The rocess of moisteningfand 'cooling dextrin w 'ch comprisesfsubjecting the dextrin t0 agitation in a vessel provided with means for circulatingfexternally thereof a currentlof a gaseousv cooling medium, circulating f erethroughv such gaseous cooling medium until the temperature of the appar, hand in the presence of two subscribing witratus is about 420 to 50 C., mixing the renesses. sulting cooling medium with steam, and subjecting the dextrin while so cooled and agi- A 5 tated to the action of the resulting mixture Witnesses:

of steam and gaseous cooling medium. GUsTAv LEDERER, In testimony whereof I hereunto set my ADELAIDE FUNK.

HEINRICH WULKAN. 

